Grab irons are used on transportation vehicles such as railroad cars to provide a support device for easy mounting and dismounting of the vehicle. Persons may hold onto the grab iron to safely enter or exit the vehicle. The grab iron may also be used in forming a step to climb onto the vehicle. In addition, a series of grab irons may be placed on a structure such as a railcar, water tower, or oil tank, forming a ladder.
In the railway industry, applicable regulations require rolling stock to have in place a full complement of undamaged grab irons for the safety of railroad personnel. Fines may be imposed by inspectors if damaged or missing grab irons are not replaced promptly. This requires the stocking of many sizes of grab irons with varying configurations. If the replacement grab iron configuration required for a particular car is not available, the freight being transported may be subject to delays in delivery while the required grab iron is ordered.
Two-piece, adjustable grab irons reduce the great deal of space and expense required to store the many one piece configurations of grab irons in case of replacement or repair, as discussed in U.S. Pat. No. 4,463,827 to Sittner. In addition, they avoid delays in ordering the desired grab iron configuration. By combining a handhold-shape, comprising a mounting flange portion and a rod member, as well as a grabfoot-shape, comprising a mounting flange portion and a base portion having a ring to receive the rod member, the grab iron is capable of meeting most if not all longitudinal distances between fastening points on railway cars. In addition, the flange portions of both pieces may have a variety of straight and offset configurations, and yet be combinable, thereby increasing the number of possible configurations.
However, the prior art embodied in the Sittner patent teaches that in order to secure the two pieces together, once they have been spaced a desired distance apart and mounted, with the rod member inserted through the ring, the rod member must be cut to an appropriate length, leaving an excess portion extending through the ring on the base, and then mechanically deformed to prevent the exit of the rod member from the ring. This structure creates several problems. First, the excess length must be properly judged in order to have sufficient material to create a sufficient bend for securing the grabfoot-shape. If the length is too short, a proper bend may not be possible. This results in an ineffective and hazardous joint or requires a new piece to be tried again. Second, even when properly made, the bend creates protrusions that can cut a worker or catch a glove, shoe or cuff when the worker is mounting or dismounting a railcar.
In addition, the prior art teaches that the base portion is formed by bending metal in a circular fashion, resulting in a ring having a center hole to receive the rod member. The ring has an incomplete torus shape. However, when the rod member is bent to secure the grabfoot-shape, the pressure exerted on the base portion has a tendency to increase the opening in the torus shape, which results in an insecure fit between the rod member and the base portion.
Accordingly, one object of the invention is to provide a two-piece, adjustable grab iron whose members are secured by the use of a metal fastener.
Another object of the invention is to provide a safe, easy, and efficient method of securing a two-piece, adjustable grab iron together.
A further object of the invention is to provide an improved base portion design where the base portion comprises a metal ring that completely surrounds the rod member, the hole in the center of the ring being formed by drilling or casting the base portion.